DR177-kit
Posted: Tue Mar 01, 2011 8:19 am
Having some problems with an engine I did for a friend.
He had a bog standard PX125 and smashed his casings to pieces on driving off a high curb and landing on the gearbox so needed a new engine.
I then found him a cheap LML reed valve 125 engine that had a big end failure so swapped the crank of his PX-engine into the LML casing, and meanwhile fitted a DR177 kit he had to the engine, along with a 24mm Spaco carb and an SIP Performance expansion he bought from SIP.
I matched the transfers on the barrel to the casing, which has much bigger transfers than a PX125-engine as standard, but apart from that didn't touch the barrel. The piston was damaged a little when I got it so I had to remove a 1/4 ich piece about 1/3 inch wide from the top side of the piston skirt. As far as I could see this shouldn't have any effect as the inlet is above the crank.
I've fitted these kits in the past to Piaggio engines and with a Sito Plus they run fairly well, but the bike I have here seems to take forever to get going and then only makes power in higher revs while the DR-kit usually has more torque.
I set the timing around the 18 degree mark and the carb has 160/BE3/122 main and a 54/160 idle jet. The jets are a big big, but not that big to cause running this poor and the piston is the right way up.
The reeds are standard LML, do I need to change these, or are the barrel and the pipe just a big mismatch?
He had a bog standard PX125 and smashed his casings to pieces on driving off a high curb and landing on the gearbox so needed a new engine.
I then found him a cheap LML reed valve 125 engine that had a big end failure so swapped the crank of his PX-engine into the LML casing, and meanwhile fitted a DR177 kit he had to the engine, along with a 24mm Spaco carb and an SIP Performance expansion he bought from SIP.
I matched the transfers on the barrel to the casing, which has much bigger transfers than a PX125-engine as standard, but apart from that didn't touch the barrel. The piston was damaged a little when I got it so I had to remove a 1/4 ich piece about 1/3 inch wide from the top side of the piston skirt. As far as I could see this shouldn't have any effect as the inlet is above the crank.
I've fitted these kits in the past to Piaggio engines and with a Sito Plus they run fairly well, but the bike I have here seems to take forever to get going and then only makes power in higher revs while the DR-kit usually has more torque.
I set the timing around the 18 degree mark and the carb has 160/BE3/122 main and a 54/160 idle jet. The jets are a big big, but not that big to cause running this poor and the piston is the right way up.
The reeds are standard LML, do I need to change these, or are the barrel and the pipe just a big mismatch?